“The disk you attached was not readable by this computer. ” can be caused by many reasons. Here are some common ones:
- The disk isn't formatted.
- The disk has a file system that's not supported on macOS.
- The disk is encrypted by BitLocker or third-party tools.
- The disk is corrupted.
- The disk is about to fail.
In your case, you likely have the SD formatted as ExFAT or FAT32, which are compatible with both macOS and Windows, right? The SD card is at least supported on macOS, as you used it with your Mac before. Also, it's unlikely encrypted.
You've mentioned that inserting the SD card on your father's PC also suggests a reformat. So, I agree with your conclusion that the SD card is corrupted.
On second thoughts, the "shitty adapter" you used may be the only thing to blame and your SD card may still be intact. So I would suggest you use the SD card with another SD card adapter and see if the error goes away.
If not, you can rely on iBoysoft Data Recovery for Mac to get your photos and videos off the corrupted SD card, then reformat the SD card to fix the corruption. This SD card recovery software is cost-effective and perfectly designed to recover data of over 1000 formats, including photos, videos, documents, audio, etc., from corrupted, unreadable, or inaccessible SD cards, USB flash drives, HDDs, SSDs, and other storage devices on Intel, T2, or Apple Silicon Macs.
You can download and install it to free preview your files before recovery.
Read more: Recover SD Card: Best SD Card Recovery Apps & Guidelines
